1. Field of the Invention
The present invention relates generally to electrical circuit module interconnecting cables and, more specifically, to an interconnecting cable utilizing a pair of flat cables adapted to form a self-supported interconnecting cable assembly.
2. Description of the Background Art
Flat flexible cables (FFCs), xe2x80x9cribbonxe2x80x9d cables and other flat cabling technologies are well known in the electronics industry as a means of electrical systems interconnection. Among the advantages provided by flat cables are simple, low cost systems assembly and ease in mass termination, since all the conductors of a flat cable are fixed in known relationship to one another in a flat, easy to handle, array. Such cables may be manufactured, for example, by coating and laminating operations or by etching or adhesive deposition techniques.
Ribbon cables, for example, are typically terminated using insulation displacement connectors to form cable assemblies suitable for interconnecting printed circuit boards, circuit modules and other electrical and electronic devices. The retention force of such insulation displacement type connectors is relatively low, often resulting in inadvertent disassembly or disconnection. This condition may be somewhat remedied by the use of locking flight cable connectors. For non-locking flat cable connectors, an adhesive is typically added to improve the retention force of the connector.
Unfortunately, the cost of a cable assembly is increased due to the use of an adhesive, though such cost increase is less than the cost of a locking connector. Additionally, the use of an adhesive increases manufacturing complexity due to the need to controllably dispense the adhesive during the mating of the flat cable and the flat cable connector. Finally, any mismatch in the thermal coefficients of expansion between the adhesive used, the cable connector and any printed circuit board (PCB) material to which the cable connector is joined will cause mechanical stresses in solder joints that may fail over time.
Therefore, it is seen to be desirable to provide a flat cable assembly in which non-locking flat cable connectors may be used without adhesives and without experiencing undue mechanical failures.
The disadvantages heretofore associated with the prior art are overcome by the present invention of a method and apparatus for providing a flat cable assembly in which two or more flat cables having respective non-orthogonal proximate terminations and respective non-orthogonal distal terminations are adapted to form a substantially straight helix structure providing a self-supporting cable assembly while reducing mechanical stresses on termination points.